Gate valve



Aug, 2, 1 927;

GATE VALVE Original Filed June 17. l92 5 2 Shuts-Sheep 1 1,637,736 R.CONRADER 2 R. CONRADER GATE VALVE 2 Sheets-Sh! ,2

Original Filed June 17. 1925 Patented Aug. 2, 1927.

nunom a commas, or am, runner-mama.

GATE VALVE.

' Application flea lane 1'), 1925, Serial No. 37,784.- Renewed October 88, 1m.

Great difficulty has been experienced in assuring a tight joint in a gate valve. This has been very largely due to the fact that the pressure seating the valve head has not been uniformly applied, or the pressure has not been well distributed. The present invention assures a uniform seating of the valve and also provides means, in its preferred form, by which the valve may be readily ground to its seat. The invention also contemplates an improved means of securing the stem to the valve and of mount ing the stem in the body. Other features and details of the invention willmore fully appearfrom the specification and claims.

The invention is illustrated in the accompanying' drawings as follows :---v

Fig.1 shows a central vertical sectionthrough the valve, said section being par allel to the seat. I

Fig. 2 a similarsection at right angles to the seat.

Fig. 3 a plan view of thevalve with the head removed.

Fig. 4.- a section on the line 44 in Figs. 1 and 2.

Fig. 5 a plan view of the valve.

Fig. 6 a perspective section of the body, the section being on the same plane as Fig. 2.

Fig. 7 an enlarged view of the rear of the valve head.

Fig. 8 a section on the line 8-8 in Fig. 7.

Fig. 9 a side elevation of the head enlaraed.

Fig. 10 a rear view of an alternative con struction of head.

Fig. 11 a bottom view, of the same.

1 marks the body of the valve. This has a passage therethrough with an inlet 2 and discharge 2 with a bonnet extension 3 and valve seat 4.

The valve head 5 is adapted to operate against the seat 4. It has the undercut slot 6 in which is arranged a nut 7, the nut being provided with a head locking it axially in the slot 6 and also locking it against turning in said slot. A stem 8 is screwthreaded and operates in a nut 7. The stem is provided with a shoulder 9 which is seated in a socket 10 in a bonnet 11. The bonnet and body have flanges 1212 and are secured together by bolts 13.

A cap 14 is secured by bolts 15 to the honnet, the bonnet having ears 16 and the cap the ears 17 through which the bolts extend. The cap locks the shoulder 9 and consea different seat so quently the stem against axial movement relatively to the bonnet. The cap also has a. stufling box 18 carrying a packin 19. A follower 20 operates in the stu through perforations in ears 23-on the follower an are screwed into screw-threaded openings 24 in cars 25 extending from the cap 14, the ears 25 being at the ears 16. p a

By providing separate bolts for securing I the cap 14 and staggering or off-setting the ears between the cap and the follower it is possible to use cap screws for the follower and consequently the heads of the screws move with the top of the follower, the space between the ears 16 permitting of the runwedging surfaces are preferably plane sur- --faces and are not only inclined toward the seat =4 but are also inclined relatively to the axis of the seat or head. In addition to this they may be and preferably are inclined toward each other. The head has a cross bar extending horizontally across it at the rear and the endsof this bar are provided with inclined surfaces 29. the general inclination of these surfaces following the inclination of the surface 27. The crossbar is rigid with relation to the valve head and the surfaces are preferably within the periphery of the head.

This arrangement of inclined surfaces,

particularly the inclination of the surface toward the axis of the valve is of very great importance. Heretoforethe common practice, Where the inclined surfaces operate directly upon a fixed portion of the valve head, has been to incline the surfaces toward the valve seat only and as a result unless the surfaces were very nicely constructed greater pressure has been delivered to one side of the valve than to the other with a consequent looseness at the one side. Further unless the valve heads have been nicely guided they have, with each seating,

that even though seating perfectly at one place they do not always I O Cap screws '21 having heads 22 extend right angles to is provided with the wedge lugs found no seat erfectl at some other place, made possi le b t e shifting of the valve. By inclining t ese engaging surfaces toward the axis of the seat, the valve head is not only moved toward its seat but is moved crosswise due to the inclination of the engaging surfaces to the axis until the wedging pressure on both sides is' equalizedand at the same time the valve head is brought to exactly the same position on the seat with each operation.

I prefer to form the surface 29 with 1 slight curve so that the valve head may be oscillated preferably by using the stem as a handle when it is desired to regrind the valve seating-surfaces. The preferable curve is that of a cone having an axis, as 30, and the axis is locatedrelatively to the engaging surface 27 as to make that engaging surface tangent to ;the cone and to have a point 31=in the line of contact between the cone and the. surface 27 in a horizontal radially extending line 32-32 so that pressure is the slot 6 and also make the opening 8" into which the screw or stem 8 extends below the nut slightly larger than the stem so that the valve head may have freedom of movement without deflecting the stem to accommodate itself to the wedge surfaces and i the seat.

In the alternative construction shown in Figs. 10 and 11 an inclined surface 33'corresponding to the surface 29 is formed as a plane surface. This surface will operate more satisfactorily than. the wedge surfaces which are in the same plane at both sides of the disc, in other words,the bevel tends to correct errors. However, unlessthese surfaces contact at both ends equally there will be an unequal pressure on different parts of the face of the valve. This result .is obviated in the preferred construction by the slight curve given to the wedging surface 29 so that the contact, orengagement is approximately diametrically opposite the center of the disc and further the slight curve permits the disc to rock slightly so as to seat perfectly and with an approximately equal pressure on all parts of the circumference.

While I have shown the axis of the cone for the surface 29 as 30, it will'be understood that it may be varied to suit the metal of WhlCh the valve is made. Where a very mamas soft metal is used it is desirable to make I the radialline longer sothat the contacting surface may more nearly approximate a plane and consequently within the elastic limit of'the metal give a greater contact surface. Where the metal is harder the cone may be formed with a shorter radius, in fact, the point 30 for the axes of the curves 29 for each side may be coincident if desired.

What I claim as new is 1. In a valve, the combination of a body; a seat in said body; a gate valve head operating on said seat; and wedging mechanism having engaging surfaces rigid with the body and head forcing the head into seating engagement with the seat as the head is moved across the axis of the seat in closing, said wedging surfaces permitting. when engaged, universal inclination-a1 freedom of the head relatively to the seat.

.2. In a valve, the combination of a body;

a seat in said body; a gate valve head op.

erating on said seat; and wedging mechanism having engaging surfaces rigid with the body and head forcing the head into seating engagement with the seat as the head is moved across the axis of the seat in closing, said wedging surfaces permitting,

when engaged, oscillating freedom of the head on the axis of the head corresponding to the axis of the seat.

, 3. In a valve, the combination of a body; aseat in said body; a gate valve head operating on said seat; and \vcdging mechanism having engaging surfaces rigid with the body and head forcing the head into seating engagement with the seat as the head is moved across the axis of the seat in closing, said wedging surfaces permitting. when engaged, universal inclinational freedom of the head relatively to the sect and oscillating freedom of the head on the axis of the head.

4. In a gate valve, the combination of a valve having a valve seat and wedging surfaces spaced from the valve seat, said surfaces being inclined toward the face of the seat and to the axis of the seat; a valve head having curved inclined surfaces, the axes of the curves being approximately parallel with the axis of the head; and means actuating the head.

5. In a gate valve, the combination of a valve having a valve seat and wedging surfaces spaced from the valve seat, said surfaces being inclined toward the face of the seat and to the axis of the seat: a. valve head having curved inclined surfaces, the axes of the curves being off-set from and approximately parallel with the axis of the head; and means actuating the head.

6. In a gate valve, the combination of a valve having a valve seat and wedging surfaces spaced from the valve seat, said surfaces being inclined toward the face of the seat and to the axis of the seat; a valve head having inclined curved surfaces rlgid with the head engaging the inclined surfaces of the body permitting universal inclinational freedom of the head relatively to the seat; and means actuating the head.

7 In a gate valve, thecombinatmn of a valve having a valve seat and wedging surfaces spaced from the valve seat, said surfaces being inclined toward the face of the seat and to the axis of the seat; a valve head having inclined curved surfaces rigid with the head engaging the inclined surfaces of the bod the axes of the curved surfaces of the hea being a proximately parallel to the axis of the head; and means actuating the head. 7

8, In a gate valve, the combination of a body having a valve seat and wedging surfaces spaced from the valve seat, said surfaces being inclined toward the face of the seat and to the axis of the seat; a valve head having curved inclined surfaces having axes off-set from the axis of the head and adapted to contact with the inclined surfaces of the body, the planes of the inclined surfaces of the body being tangential to the curved surfaces at the points of contact; and means actuating the head.

9. In a gate valve, the combination of a body having a valve seat and wedging' surfaces spaced from the valve seat, said surfaces being inclined toward the face of the seat and to the axis of the seat; a valve head having curved inclined surfaces having axes off-set from the axis of the head and adapted to contact with the inclined surfaces of the body, the planes of the inclined surfaces of the body being tangential to the curved surfaces at the points of contact, with the points of contact between the inclined surfaces of the head and the inclined surfaces of the body at diametrically opposite sides of the plentpr of the head; and means actuating the ea a i 1 '10. In a gate valve, the combination of a. body havin a valve seat and wedgin surfaces spaced from the valve seat, sai surfaces being inclined toward the face of the seat and to the-axis of the seat; a valve head having curved inclined surfaces having axes off-set from the axis of the head, with the planes of the inclined surfaces of the body tangential to the curved surfaces of the head at the points of contact and the points of contact being at diametrically opposite sides of the axis of the head; and means for actuating the head.

11. In a gate valve, the combination of a valve havin a valve seat and wedging surfaces space from the valve seat, said surfaces being inclined toward the face of the seat and to the axis of the seat; a valve head having curved inclined surfaces, the axes of the curves being approximately parallel with the axis of the head; and a stem actuating the valve and adapted to oscillate the same. 12. In a gate valve, the combinaton of a body; a seat in the body; a gate valve head operating on said seat; and wedging mechanism having engaging surfaces on the head and body forcing the head into seating engagement with the seat as the head is moved across theaxis of the seat in closing, said wcdgin surfaces when engaged permitting oscillating freedom of the head in the plane of the'seatingsurfaces. v

13. In a gate valve, the combination of a body; a seat in the body; a gate valve head operating on said seat; and wedging mecha nlsm having engaging surfaces on the head and body centering the head, forcing the head into seating engagement with the seat as the head is moved across the axis of the seat in closing, said wedging surfaces when engaged ermitting oscillating freedom of the head 1n the plane of the seating surfaces.

In testimony whereof I have hereunto set my hand.

RUDOLPH CONRADER. 

